// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_LIBPLATFORM_TRACING_TRACE_BUFFER_H_
#define V8_LIBPLATFORM_TRACING_TRACE_BUFFER_H_

#include <memory>
#include <vector>

#include "include/libplatform/v8-tracing.h"
#include "src/base/platform/mutex.h"

namespace v8 {
namespace platform {
    namespace tracing {

        class TraceBufferRingBuffer : public TraceBuffer {
        public:
            TraceBufferRingBuffer(size_t max_chunks, TraceWriter* trace_writer);
            ~TraceBufferRingBuffer() override = default;

            TraceObject* AddTraceEvent(uint64_t* handle) override;
            TraceObject* GetEventByHandle(uint64_t handle) override;
            bool Flush() override;

        private:
            uint64_t MakeHandle(size_t chunk_index, uint32_t chunk_seq,
                size_t event_index) const;
            void ExtractHandle(uint64_t handle, size_t* chunk_index, uint32_t* chunk_seq,
                size_t* event_index) const;
            size_t Capacity() const { return max_chunks_ * TraceBufferChunk::kChunkSize; }
            size_t NextChunkIndex(size_t index) const;

            mutable base::Mutex mutex_;
            size_t max_chunks_;
            std::unique_ptr<TraceWriter> trace_writer_;
            std::vector<std::unique_ptr<TraceBufferChunk>> chunks_;
            size_t chunk_index_;
            bool is_empty_ = true;
            uint32_t current_chunk_seq_ = 1;
        };

    } // namespace tracing
} // namespace platform
} // namespace v8

#endif // V8_LIBPLATFORM_TRACING_TRACE_BUFFER_H_
